[PATCH] mpi: Drop casts from inline asm output operands.

[NIIBE Yutaka]

Hello,

Matt Turner wrote:
> Using a cast as an lvalue is a GCC extension that clang does not
> implement.  Clang rejects it with -Winvalid-gnu-asm-cast, which is an
> error by default, so these blocks fail to build with clang.

Please find a workaround for Clang.  IIUC, please use
-Wno-invalid-gnu-asm-cast option.  If really needed, we could consider
adding the option for Clang in libgcrypt/configure.ac.

For longlong.h, the upstream used to be GNU C library.  It is GCC now
(gcc/include/longlong.h).

We don't want further differences of our own from upstream.
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